With RadGrid data-bound to a RadClientDataSource you can have an entirely
client-side grouping functionality and avoid unnecessary postbacks to the server. Integrating those two controls allows
fast grouping to be performed directly on client-side, without losing any
of the supported with server-side grouping features (like adding, removing or rearranging groups, collapsing, expanding, etc.).

For enabling client-side grouping, you just need to have a properly configured RadClientDataSource control and set the
ClientDataSourceID property of RadGrid. In the same manner as with server-side grouping,
you can have predefined groups in GroupByExpressions (by adding data fields in SelectFields and/or
GroupByFields within GridGroupByExpression) or allow the user to drag and drop columns to the GroupPanel.